Crusher and pressure-exerting machinery



May I1, 1937. s, w TRAYLQR. J 2,079,882

CRUSHER AND PRESSURE EXERTING MACHINERY Filed Sept. 50, 1931 3 Sheets-Sheet l WITNESSES INVEN TOR:

Same] wzlzmyia hm ATTORNEYS.

y 1937- Y s. w. TRAYLOR, JR 2,079,882

QRUSHER AND PRESSURE EXERTING MACHINERY Filed Sept. 30, 1931 3 Sheets-Sheet 2 g E k K) "Q 5% MW w E g a $38;

Q g N Q Q4 m a ma fifi w E May 11, 1937;

WITNESSES QJMJW S. W. TRAYLOR. JR

CRUSHER AND PRESSURE EXERTING MACHINERY Filed Sept. 50, 1951,

FIG I.

25k 2 25g 25 L 25 6 3 Sheets-Sheet 5 I N VEN TOR:

TORNEYS.

Patented May 11 1937 UNITED STATES PATENT OFFICE CRUSHER AND PRESSURE-EXERTING MACHINERY Delaware Application September so, 1931. Serial No. scam 21 Claims.

The invention relates to gyratory crushers, and to the regulation oi working pressure and stress in crushing or pressure-exerting machinery. The invention-aifords a simple and compact crusher that is easy and economical to build, and can be made very rugged and powerful. The invention affords a new way of adjusting such machinery according to the degree of flneness or coarseness of product desired, and of controlling the working pressure and preventing excessive .pressures and stresses.

In the drawings, Fig. I is a vertical section through a gyratory crusher and associated apparatus, embodying my invention.

Fig. II is a vertical section of a modification.

Fig. III is a fragmentary vertical sectional view of the lower portion of the device shown in Fig. II, with certain parts in full that are there shown in section.

Fig. IV is a similar view illustrating another modification.

Fig. V is a vertical mid-section illustrating a different type of crusher from that shown in Fig. I. i

The crusher shown in Fig. I comprises a crushing hopper or shell l located in the upper portion of the hollow frame or casing H, and a gyratory member l2 provided with a crushing head l3 gyrating in the shell l0, and cooperating therewith to crush material in the varying interval between them. The gyratory member i2 is actuated by a rotary eccentric H, which is engaged or journalled around the shaft portion l5 of the member I2 below its head I3, and is externally journaled in a hub-like structure l8. In the present instance, the shaft I5 is shown integral with the head l3. 'Ihe hub I6 is connected to the frame or casing II by spoke-like webs i1 and a hollow countershaft bearing boss l8,all preferably cast integral with the frame The gyratory member .l2or a downward extension 20 of its shaft portion l5--has its neutral, non-gyrating point of no throw 2| in the lower portion of the casing II, where its lower end engages and rests on a bearing disc 22 seated in a depression in the upper end of a supporting boss 23. The boss 23 forms part of a hollow drum-like bottom structure 24 that is suitably secured to the lower end of the hub i6. Provision may be made to prevent the shaft extension 20 from turning, as by anti-turning engagement of an angular (square) form of projection 21a on the extension 20 in a correspondingly formed socket in disc 22 and boss 23. If desired, radial oil grooves may be provided at 2|, at suitable intervals in the lower end surface of the extension member 20 and in the coacting bearing surface at 22, to permit oil to work in between them more readily.

The eccentric H has an external step bearing shoulder 25 that rests on a step bearing formed by one or more bronze rings 26 seated in a rabbeted seat on an internal flange 28a at the upper endoi' the bottom 2|. On the eccentric l4, Just above the step bearing 25, is a bevel driving gear 21 that meshes with a bevel pinion 28 on the inner end of a countershaft 29 mounted in a bearing bracket structure 30, which is mounted and secured in the bore of the boss l8. The countershaft 29 may be driven from any suitable source of power, to rotate the eccentric M.

As shown in Fig. I, the shaft l5 of thegyratory member i2 is hollow and the extension 20 telescopes therein with a sliding flt, like a plunger, so that parts l2 and 20 together form a gyratory member that is variable in length, though substantially inflexible laterally as if they were one solid shaft,like the gyratory member I2 01 Figs. II-V. Hydraulic packing 39 is provided at the upper end of the member 20 to make a fluid-tight joint. To facilitate removal of'the gyratory parts from the crusher. a lost-motion connection of the extension 20 to the member l2 may be provided, consisting of a rod 32 screwed into the upper end of the member 20 and extending up through a bore in the member I2 to an enlarged and diametrically grooved head 33 loosely accommodated in a recess 34 in the head IS. A removable screw plug 35 and cap 38 afford access to the head 33 when necessary. To shift the parts 20 and l5, II in the axial direction relative to one another, fluid can be admitted to the cylinder bore 40 of the member I2, above the plunger 20 (or vented therefrom), through a duct 4| extending down through the center of the plunger and its non-gyrating engaging portion Zia, with a flexible tube connection 42 from its lower end out through the bottom structure 24 to a pipe connection 44. Thus the effective length of the gyratory member l2 can be varied, and the head l3 can be raised and lowered relative to the shell ill to vary and regulate the size of the crushed product. In other words, the cylinder bore 40 and its plunger 20 constitute a hydraulic motor for varying the effective length of the gyratory member l2, and raising and lowering the crushing head l3. Against normal crushing stresses, the head ll can be flrmly sustained by the fluid, while by yielding of this fluid support under abnormal working stresses, the shaft and head can be allowed to recede downward, to relieve such stresses and protect the machine against damage from tramp iron getting in the crushing shell I8, or the like.

The fluid supply and discharge pipe 44 is shown connected to the delivery side of a plunger or other pump 45, provided with intake and discharge check valves 46, 41, and drawing from the bottom of a supply vessel 48. The pump 45 may be run continuously whenever the crusher is in operation, or it may be run intermittently, when and as required. As-here shown, the vessel 48 includes two compartments or receivers 58, 5|, the former open but provided with a removable cover 52, and the latter closed. From the bottom. of

the open (upper) receiver 58, there is a delivery connection to the closed (lower) receiver 5|, controlled by a hand valve 54. The receiver 5| is provided with a drain connection and valve 55. From the delivery side of the pump 45 and its discharge valve 41, there are bye-pass connections to the receivers 58, 5|, through a pipe 58 with branches 51, 58. In the connection 51 of the receiver 58, there is a stop hand valve 59; while in the connection 58 to the receiver 5|, there is an automatic pressure-controlled relief valve 68. A pressure gauge 6| may be connected to the connection 56, if desired, to show the pressure in the high-pressure side of the system. The receiver 5| may be provided with a hand-valve controlled air vent 62 from its highest point.

As here shown, the lower end of the crushing head I8 has a cylindrical surfaced internal shoulder or cavity formed by a depending skirt or flange 65. The corresponding portion of the hub I5 has an external annular groove 66, in which is mounted a sealing ring 68 whose cylindrical periphery engages with the cylindrical inner surface of the head l3 at 65. The coacting surfaces of the ring 61 and of the sides of its groove 56 are preferably spherical, and concentric with the neutral point of the member I2 at 2|. The ring 61 permits free gyratory movement of the head l3, and does not interfere with its vertical adjustment, but nevertheless forms a tight seal between the head I3 and the hub I6 against ingress of dust or dirt and against egress of oil or lubricant. In the present instance, similar sealing is provided between the exterior surface of the gyratory shaft l5 and the upper end of the hub I6, by means of a sealing ring 68 mounted in an internal annular groove 69 between shoulders at the upper end of a (separate) bearing liner or bushing 18 in the hub I6. The inner cylindrical surface of the ring 68 engages the cylindrical outer surface of the shaft I5. The coacting surfaces of ring 68 and of the sides of its groove 69 are preferably spherical and concentric with the neutral point 2|.

While either of the seals 61 and 68 might be omitted, their combination presents important advantages. Without the seal 68, oil working or thrown upward, above the eccentric l4 and hub I6, would run down on the seal 61 and work its way down past the latter, caking dust below it into a ridge or shoulder that would have to be broken away whenever the head l3 was raised after prolonged operation at one setting. Without the seal 61, dust would have access to the shaft I5 above the seal 68, and oil creeping up past the seal 68 would cake such dust into a ridge or shoulder above the seal 68 that would have to be broken away on lowering the head l3.

Failure of these caked dust ridges to break away clean would tend to injure and impair the effectiveness of the seal rings 61, 88.

From the foregoing description, it will be seen that the operating mechanism (eccentric I4, gears 21, 28, neutral bearing and support at 2|, 22, etc.) is all enclosed and sealed in the interior of the crusher, in the chamber afforded by the hub l6 and bottom structure 24. Thus all the working and wearing parts and surfaces are enclosed and included in the main lubricating system of the crusher, and thoroughly lubricated. When the crusher is at rest, the oil supply in the enclosure forms a pool that extends up upon the teeth of the gear 21; when the crusher is in operation, the oil level is lower, but still extends above the lower end of a helical groove 12 (of comparatively large pitch) in the external surface of the shaft I5. During the operation of the crusher, therefore, oil is lifted into the interior of the eccentric by the groove 12, and is raised or wiped upward in the groove by the combined action of centrifugal force and of friction between the interior of the revolving eccentric and the exterior of the shaft |5,-which does not revvolve,thoroughly lubricating the interior of the eccentric, Reaching the top of the eccentric I4,

the oil descends in grooves 18 in the bearing surface of the bushing 18, thoroughly lubricating it.

Some of this oil flows outward over the teeth of gear 21, lubricating its contact with pinion 28. Oil also flows down and out through a port or passage 14 in sleeve 18 and hub I6 to a chamber 15 in the bearing bracket 38, whence it runs through ports 16 to the countershaft 28. This oil works its way inward and outward through the countershaft bearings, and finally returns through ports 11, 18, 19 to the pool beneath the gear 21.

As shown, there is an annular baffle 88 depending from the flange 26a of the bottom drum 24, and extending down to a considerable depth in the oil pool. In the pool, and preferably in the path of circulation produced by the baffle 68, cooling means may be provided, here shown as located inside the baflle 88, and as consisting of a double helical pipe coil 83, with supply and discharge connections 84, 85 down through the bottom of the drum 24, for the circulation of cooling water. As shown, the coil convolutions 83 are mounted in openings in suitably constructed ribs or radial baffles 86, located at such circumferential intervals as to support the coils properly. Below the bearing 23 and the baffle 88 is a dead space, around the boss 24, for dirt to settle out of the oil fiow.

The downward-flared crushing shell I8 may be surfaced with a separate lining 98 (usually termed a concave") removably mounted in the upper end of the frame or casing II, which latter may be made in one piece. The concave 98 can also be made in one piece or without vertical division: as here shown, it consists of a single annular member, held in place by superjacent annular securing means 9|. The concave I8 is flared downward externallyas well as internally: accordingly, the securing means 9| is shown of a corresponding wedge section, to fit in the cylindrically bored upper portion of the frame around the concave 98, and hold the latter securely. The frame II and the wedge means 9| are shown with external flanges 92, 93, through which extend securing bolts 94, The frame II is internally shouldered at 95, as a means of seating and sustaining the concave 98 in the frame. The circular wedge 9| has a sliding fit in the frame II,

and has its inner conical surface machined to 75 fit the concave 90, which may be a ground machine fit in said part 9|, or may have a supporting filler of spelter, or any other means of making a joint. The frame II is taper bored at 95 in conformity to the conical edge of the concave 90. By pulling up the bolts 94 tightly, the wedge flange 93 is drawn to frame flange 92, the wedge 9| is clamped in the frame II, and the concave 90 is forced home and held securely against movement due to the crushing stresses.

The wedge means 9| may, if desired, be split at several points, to facilitate its removal from the frame I I when required. The rim 93 may be protected from wear by wearing plates 96. By operating the crusher after loosening the bolts 94, the wedge means 9| and the concave 90 will be loosened in the frame so as to be easily lifted out.

In the operation of the crusher, the point of greatest motion of the gyratory member I2 is at the top, in the head l3, while the point of nomotion is at the bottom, at 2|, and the eccentric and its external bearing in the hub l6 are intermediately located, close below the head. This not only allows the usual spider support above the head l3 to be eliminated, but also allows a heavier and stronger shaft |5 to be used, and an eccentric I4 of larger diameter, smaller throw, and greater power, and also of more ample hearing surface for a given axial length. This follows from the fact that the gyratory throw of the head I 3 exceeds that of the eccentric I4, instead of being less, as in the ordinary crusher with fulcrum at the top and eccentric at the bottom. This naturally results from the location of the neutral point of no throw of the member I2 below the eccentric l4, at the neutral no-throw bearings 2|, 22. The point 2| is made thus neutral by internally boring the eccentric M to an axis X which would intersect the axis X of the external surface of the eccentric at 2| 1. e., an axis X suitably inclined relative to the axis X of the external surface of the eccentric.

With respect to vertical adjustment and automatic protection against excessive stresses due to the presence of "tramp iron or the like in the crushing shell l0, it will be seen that while the gyratory member |2 has a fixed neutral point of no-throw engagement and support at 2|, yet it can be varied in effective length to raise and lower the head,either to adjust for fine and coarse crushing, or to protect the crusher from damage by excessive crushing stresses,-by the action of the variable hydraulic support or motor at 40, which is both adjustable and automatically yielding as hereinafter explained.

Supposing that the crusher and the pump have been shut down, and the valves 59, 54, and 55 opened, the gyratory head l3 and shaft l5 will be resting on the central upper surface of the plunger 20, and the compartments 50, 5| will both be empty. When the crusher is to be used, the valves 59 and 55 are closed, the pump 45 is started (either by its own motor, or by the starting of the crusher, if the pump is driven therefrom), and a liquid, such as oil, is put into the compartment 50. The valve 54 being open, or presently opened, the oil will run down. into the receiver 5|, and (as fast as it reaches the receiver 5|.) drawn off by the pump 45 and forced into the cylinder 40, raising the crushing head l3 correspondingly. When the desired adjustment of the head I3 is thus reached (to give the desired size of product), the valve 54 is closed. The relief valve being suitably adjusted, the oil will be held confined, and the head l3 fixedly supported at the desired height under the normal working pressure. If it isdesired to raise the head l3 higher, the valve 54 will be opened, and more oil will be pumped into the cylinder 40; if it is desired to lower the head, the valve 59 will be opened until the necessary amount of oil has been drawn off into the receiver 50. By keeping a definite amount of oil in the system, the crusher can always be reset to a desired maximum fincness of product by merely opening the valve 54 and leaving it open.

If tramp iron or other hard material in the shell I0 gives rise to excessive working thrust and pressure, the relief valve 60 will open and allow the head l3 to yield,-the oil thus vented from the cylinder 4|] flowing back through the bye-pass 55, 58 to the receiver 5| and short-circulating through this by-pass as long as the working pressure and thrust in the machine remain unduly high. Whenever the abnormal condition is relieved, the oil is automatically repumped back into the cylinder 40, and the crusher thus restored to its intended working adjustment.

I When all the oil has been forced into the pressure line by the pump 45, the latter will draw in air on the subsequent suction stroke; but this air will not be compressed sufficiently to enter the line on the succeeding working stroke-the pump displacement and clearance being so chosen as to assure this.

Figs. II and III illustrate another simple way of adjusting a crusher of the general type shown in Fig. I. Here the telescopic shaft extension or plunger 20 of Fig. I is dispensed with, and the lower end |5a of the main gyratory shaft |5 (which is solid) rests directly on the bearing support disc 22, which is vertically adjustable, and may be engaged therein at 2|a. The disk 22 rests on a plunger 23a which is mounted ina cylinder bore or guide 23b in the boss 23 of the bottom structure 24, and is supported by a screw 23c threaded through the bottom structure 24, like a set-screw. As shown, the disc 22 is engaged and guided in an enlargement of the bore 23b. By screwing the screw 23c up and down, theshaft l5 and the whole gyratory member can be vertically adjusted to vary and regulate the fineness or coarseness of the crushed product.

If desired, the plunger 23a may be equipped with hydraulic packing 23d and the cylinder 2311 may have a pressure fiuid connection 44 to a system such as shown in Fig. I. This allows the vertical adjustment to be made hydraulically, and also permits automatic yielding and recession of the head l3 as in Fig. I. Thus the screw 23c becomes no more than a clean-out plug, or a stop for limiting the coarsening adjustment by fiuid. Any preferred means may, of course, be used to introduce and draw off fiuid from the cylinder 231).

Fig. IV illustrates an arrangement similar to Figs. II and III, but embodying a spring cushion support arrangement in lieu of the simple solid plunger of Figs. II and III. For this purpose. there are plunger members 23e, 23f with interposed helical compression'springs 239, whose ends are seated in recesses 23h in the members 23e, 23f. The members 23e, 23 are interconnected by tension bolts 232' whose conical heads 23 are engaged and accommodated in conical counterbores 23k in the member 23e, and whose nuts 231 are accommodated in recesses 23m in the member 23 The bolts 231' may preferably extend through the springs 23g. When the cushion device is put in place, its springs 239 are pretensioned, by the bolts 23:, to sustain the normal crushing stresses without yielding; but if excessive stresses are encountered, the springs yield and afford relief and protection.

If desired, hydraulic packing 23d may be provided on plunger member 23c, and a fluid connection 44, allowing the device to be adjusted by fluid as indicated in connection with Fig. II.

Fig. V illustrates fluid support and adjustment arrangements applied to a more ordinary type of crusher, whose shaft l5 extends above the head l3 at lib and is there engaged in a spider IOUa, so that the greatest motion of the gyratory member I2 is at the lower end, which is actuated by the eccentric Ma. The gyratory member I2 is not supported from the bottom, as in Fig. I, but from the top, i. e., the fluid cylinder and plunger are at the top of the gyratory shaft I5b, whose lower end may be directly engaged and actuated to gyrate the gyratory member l2, without any plunger extension 20 or 20a. In this case, the split tapered nut lllla in the taper bore of the sleeve [02a is screwed directly on the upper end of the shaft lib, and the lower end of the sleeve l02a constitutes an annular plunger in an annular cylinder bore in an annular member Iota. Accordingly, the annular plunger I021: may be provided with external and internal hydraulic packings 39b, 390, to make tight joints with the walls of the cylinder 14a. The cylinder member lMa rests and gyrates (with the plunger i02a) on a wearing ring l03a mounted in the spider lfllla. Fluid (oil) under pressure is admitted and vented to and from the cylinder [04a through a duct I06 in the plunger IBM, to which there is a flexible connection I 01 leading, through a swivel connector or universal 42a, to a pressure connection 44 of a system such as shown in Fig. I, or to any suitable means of introducing and drawing off the pressure fluid. Oil admission to the cylinder 4!! raises the head l5 relative to the crushing shell l0, and vice-versa.

As mentioned above, this Fig. V crusher is of the more ordinary and well-known type in which the upper end of the gyratory member I2 is fulcrumed in the spider hub a, and the eccentric I4a, imparts the greatest motion to the lower end of said member I2. Ma and plunger I02a constitute a (hydraulic) motor for raising and lowering the crushing head 13, and thereby also varying the effective length of the gyratory member l2,

In each of Figs. II-V, various parts and features are marked with the same reference character as corresponding parts and features in Fig. I or in other figures (sometimes with an added letter, a, b, etc.) as a means of dispensing with merely repetitive description.

Having thus described my invention, I claim:

1. A gyratory crusher comprising a frame with a crushing shell, a hub, and a subjacent bearing; a rotary eccentric in said hub with the axes of its external and internal surfaces intersecting in a neutral point of no-throw at said bearing; a substantially inflexible gyratory member engaged in said eccentric, and engaging said bearing at said neutral point, and having a crushing head in said shell above said eccentric and hub; and annular sealing means coacting with said hub and said gyratory member to exclude dust from said eccentric while permitting gyration and vertical adjustment of the head. a

2. A gyratory crusher comprising a frame with a crushing shell, a hub, and a subjacent bearing;

In other words, the cylinder ao'rasss a rotary eccentric in said hub with the axes of its external and internal surfaces intersecting in a neutral point of no-throw at said bearing; a gyratory member including a shaft in said eccentric engaging said bearing at said neutral point, and a crushing head in said shell, above said eccentric and hub, hollowed at "its lower side to afford a skirt around the upper end of said hub; annular sealing means coacting with said hub and shaft to exclude dust or dirt from said eccentric while permitting gyration and vertical adjustment; and other annular sealing means similarly coacting with said hub and skirt.

3. A gyratory crusher comprising a crushing shell, a substantially inflexible gyratory member including a crushing head gyrating in said shell, so as to vary their interval and crush material between them, a bearing for said member below said head; a rotary actuating eccentric around and engaging said inflexible gyratory member intermediate said head and bearing, with the axes of its external and internal surfaces intersecting in a neutral point of no-throw at said bearing, and supporting means for said bearing adjustable up and down to raise and lower the crushing head in the shell.

4. A gyratory crusher comprising a crushing shell, a flxed supporting bearing, a gyratory member having a crushing head in said shell and engaging said supporting bearing at a substantially 3 flxed, invariable point of no-throw of the said gyratory member, an eccentric for imparting gyratory movement to said gyratory member, and means for varying the length of said gyratory member between its head and its said fixed, no-

throw point of engagement with said bearing even during the operation of the crusher and the gyratory movement of the member.

5. A gyratory crusher comprising a crushing shell; a gyratory member having a crushing head in said shell and supported at its own lower end; means for adjusting the length of said gyratory member between its head and its support; and a rotary eccentric for gyrating said member engaged around it below its head.

6. A gyratory crusher comprising a crushing shell; a gyratory member including a crushing head in said shell having a shaft and a downward extension of said shaft supported below the same,

said shaft'and extension being relatively shiftable in the axial direction; means for relatively shifting said shaft and extension as aforesaid, and a rotary eccentric around said shaft for gyrating said member and head.

7. A gyratory crusher comprising a crushing shell; a gyratory member including a crushing head in said shell having a shaft, and a downward extension of said shaft supported at its own lower end, said shaft and extension being telescopically interengaged and relatively shiftable in the axial direction; means for relatively shifting said shaft and extension as aforesaid; a rotary eccentric engaged around said gyratory member for gyrating it, with the axes of its external and internal surfaces intersecting in a neutral point of no-throw at the lower end of said extension; and a no-throw bearing for said gyratory member at said neutral point.

8. A gyratory crusher comprising a crushing shell; a gyratory member including a crushing head in said shell having a shaft and a downward extension of said shaft supported below the same and held against turning, while free to gyrate, said shaft and extension being relatively shiftable in the axial direction; means for relatively shifting said shaft and extension as aforesaid, and a rotary eccentric engaged around said gyratory member for gyrating it, the axes of the external and internal surfaces of said eccentric intersecting in a neutral point of no-throw at the point of support of said extension.

9. A gyratory crusher comprising a crushing shell, a telescopically expansible and contractible gyratory member including a crushing head gyrating in said shell, means for imparting gyratory movement to said gyratory member, and means including a hydraulic motor in said member for telescopically expanding and contracting the same, and thus varying its effective length.

10. A gyratory crusher comprising a crushing shell, a gyratory member including a crushing head gyrating in said shell, a hydraulic support for said member including a gyrating cylinder and plunger telescoped one within the other, and means for introducing and venting fiuid to and from said cylinder through said plunger.

11. A gyratory crusher comprising a crushing shell, a gyratory member including a crushing head in the shell and a hollow shaft, a plunger in the hollow of said shaft, supporting means for the lower end of said plunger, means for gyrating said gyratory member, and means for introducing and venting fluid to and from the hollow of said shaft.

12. A gyratory crusher comprising a crushing shell, a gyratory member including a crushing head in the shell and a hollow shaft, a plunger in the hollow of said shaft, supporting means for the lower end of said plunger, means for gyrating said gyratory member about a neutral point of no-throw, and means for introducing and venting fluid to and from the hollow of said shaft through the neutral point of said member.

13. A gyratory crusher comprising a crushing.

shell, a gyratory member including a crushing head in the shell and a hollow shaft, 9. plunger in the hollow of said shaft, a bearing support at the lower end of said plunger, said plunger and said support being anti-rotatively interengaged, means for gyrating said gyratory member about a neutral point of no-throw at said bearing support, and a flexible connection to the neutral point of said plunger for introducing and venting fluid to and from the hollow of said shaft.

14. A gyratory crusher comprising a crushing shell, a substantially inflexible gyratory member including a crushing head gyrating in said shell, so as to vary their interval and crush material between them, and having a neutral point of nothrow at the lower end of the gyratory member, a no-throw bearing and spring cushion means for yieldingly supporting the lower end of said gyratory member, and a rotary actuating eccentric around said member intermediate said head and bearing.

15. A gyratory crusher comprising a crushing shell, a substantially inflexible gyratory member including a crushing head gyrating in said shell,

i so as to vary their interval and crush material 1 between them, and having a neutral point of no ber including a crushing head gyrating in said shell, so as to vary their interval and crush material between them, of a hydraulic pressure system including means for sustaining the normal working pressure betweensald head and shell; pressure relief means for automatically venting liquid out of said pressure system under excessive working pressure due to hard material between said head and the crushing shell, thustemporarily allowing said head to yield and recede downward; and means including a pump for automatically delivering liquid under pressure into said system when the excessive working pressure is over, until said crushing head is restored to normal working position.

17. The combination with a gyratory crusher comprising a crushing shell and a gyratory member including a crushing head gyrating in said shell, so as to vary their interval and crush material between them, of hydraulic means for sustaining the working pressure between-said head and shell, a pump for delivering liquid to said means under normal working pressure, and automatic relief means for by-passing and returning the pumped liquid from said means to the intake of said pump and thus allowing the gyratory head to yield and recede downward under excessive working pressure due to hard material between said head and the crushing shell.

18. The combination with a gyratory crusher comprising a crushing shell and a gyratory member including a crushing head gyrating in said shell, so as to vary their interval and crush material between them, of hydraulic means for sustaining the working pressure between said head and shell, a pump for delivering liquid to said.v

means under normal working pressure, a liquid supply system including a receiver connected to the intake of said pump, and automatic relief means for by-passing and returning the pumped liquid from the delivery side of said pump back to said receiver and thus allowing the gyratory head to yield and recede downward under excessive working pressure due to hard material between said head and the crushing shell.

19. The combination with a gyratory crusher comprising a crushing shell and a gyratory member including a crushing head gyrating in said shell, so as to vary their interval and crush material between them, of hydraulic means for sustaining the working pressure between said head and shell, a pump for delivering liquid to said means under normal working pressure, a liquid supply system including a receiver connected to the intake of said pump, automatic relief means for by-passing and returning the pumped liquid from the delivery side of said pump back to said receiver, and thus allowing the gyratory head to yield and recede downward under excessive working pressure due to hard material between said head and the crushing shell, and manually controlled means for returning liquid from said hydraulic means back to said supply system.

20. The combination with a gyratory crusher comprising a crushing shell and a gyratory member including a crushing head gyrating in said shell, so as to vary their interval and crush material between them, of hydraulic means for sustaining the working pressure between said head and shell, a pump for delivering liquid to said means under normal working pressure, a liquid supply system including a closed receiver connected to the intake of said pump, an open receiver with a manually controlled connection for delivering into said closed receiver, automatic 10 a gyrating cylinder and plunger telescoped one within the other, a system including a pump for delivering liquid to said cylinder under normal working pressure, and automatic relief means for venting the pumped liquid from said system and thus allowing the gyratory head to yield and recede downward under excessive working pressure due to hard material between said head and the crushing shell.

SAMUEL WILLIAM TRAYLOR, JR. 

